(a) Field of the Invention
The present invention relates to a power plant supporting mount which insulates a power plant such as an engine or a transmission from the vehicle frame so that vibrations are not conveyed therebetween. More particularly, the present invention relates to a power plant supporting mount which effectively restricts rolling of an engine or transmission in which the same vibrate in a predetermined direction in relation to the frame.
(b) Description of the Prior Art
Referring to FIG. 1, shown is a sectional view of a conventional power plant supporting mount.
As shown in the drawing, the conventional power plant supporting mount comprises an inner pipe 52 connected to the frame, and an outer pipe 53 connected to the power plant, i.e., the engine or transmission. A vibration absorbing member 54 made of an elastic material is provided between the inner pipe 52 and the outer pipe 53. Further, a plate-shaped rolling restriction member 55 is integrally formed on an outside circumference of the inner pipe 52 such that the rolling restriction member 55 is also connected to the frame, and surrounds opposing ends of the outer pipe 53 and the vibration absorbing member 54. The rolling restriction member 55 restricts the vibration of an engine or transmission bracket (not shown) when the same exceeds a predetermined degree of movement.
In the prior art power plant supporting mount structured as in the above, when rolling occurs between the frame and the engine or transmission such that the outer pipe 53 moves in relation to the inner pipe 52, the elastic vibration absorbing member 54 interposed between the inner pipe 52 and the outer pipe 53 absorbs the vibrations generated by the rolling operation. Accordingly, rolling is quickly offset and suppressed.
Here, if the movement of the outer pipe 53 in relation to the inner pipe 52 is substantial (namely, if there is a large amount of rolling), the outer pipe 53 and the engine or transmission bracket connected to the outer pipe 53 comes into contact with the rolling restriction member 55. As a result, large vibrations of the outer pipe 53 and the engine or transmission bracket are prevented. Moreover, because the collision of the outer pipe 53 and the engine or transmission bracket with the rolling restriction member 55 causes the generation of shock, a rubber stopper 56 is disposed on the inner pipe 52 between the rolling restriction member 55 and the outer pipe 53.
However, the rubber stopper 56 does not sufficiently absorb the shock generated by the collision of the outer pipe 53 and the engine or transmission bracket with the rolling restriction member 55.